Thread: Why use an X-pattern on a wide hone?

WOW, Russel, those are some nice pictures you showed us.

I have been thinkering about this some more today.
I wonder if there is any "sawing" action while cutting a hair with a razor. I guess we all know that a saw works by tearing fibers and cells out of the material it is cutting, making a kerf that, when it reaches the far end of the material, separates it into two parts. Cutting does the same, but without removing any material. The wedge of the cutting bevel forces the cells apart, and always separates two adjacent cells. If I have this right, one cell is never being cut in half. It are always two cells that are being separated.
On the premise that there is NO sawing action (something I can only assume, but not know for a fact), the striations have to be there for another function.
What Alan said makes a lot of sense too me, but I don't think it's the only principle at work here.
The outer layer of a hair is made out of microscopical overlapping cuticular scale-like cells. In order to cut a hair the razor must grab between two of those overlapping cells. I think the saw tooth pattern might play a key role when it comes to "catching" between two cuticular cells. That would explain why a scything motion cuts better. When the razor is dragged across there's a much bigger chance that a "teeth" grabs a cuticular scale and pulls it aside enough for the cutting wedge to find its way in.
Without a scything motion there's a greater chance that the razor skates over a few cuticular scales before it is able to force its way in. It would also explain why ATG shaves closer then WTG. ATG being against the direction of the scales as well. It would also mean that the scything motion is less important when going ATG. I think.
This is just a theory.
Luckily one doesn't have to understand the principles of the combustion engine on a subatomic level, in order to know how to drive a car... I would be one lousy driver

Bart.